Add support for binding to IPv6 localhost in `flutter run` (#13136)

This allows `flutter run` to work on hosts that are IPv6-only.

packages/flutter_tools/lib/src/android/android_device.dart

@@ -345,6 +345,7 @@ class AndroidDevice extends Device {
     bool prebuiltApplication: false,
     bool applicationNeedsRebuild: false,
     bool usesTerminalUi: true,
+    bool ipv6: false,
   }) async {
     if (!await _checkForSupportedAdbVersion() || !await _checkForSupportedAndroidVersion())
       return new LaunchResult.failed();
@@ -381,7 +382,11 @@ class AndroidDevice extends Device {
       // TODO(devoncarew): Remember the forwarding information (so we can later remove the
       // port forwarding or set it up again when adb fails on us).
       observatoryDiscovery = new ProtocolDiscovery.observatory(
-        getLogReader(), portForwarder: portForwarder, hostPort: debuggingOptions.observatoryPort);
+        getLogReader(),
+        portForwarder: portForwarder,
+        hostPort: debuggingOptions.observatoryPort,
+        ipv6: ipv6,
+      );
     }
 
     List<String> cmd;

packages/flutter_tools/lib/src/commands/run.dart

@@ -28,6 +28,12 @@ abstract class RunCommandBase extends FlutterCommand {
         negatable: true,
         defaultsTo: false,
         help: 'Start tracing during startup.');
+    argParser.addFlag('ipv6',
+        hide: true,
+        negatable: false,
+        defaultsTo: false,
+        help: 'Binds to IPv6 localhost instead of IPv4 when the flutter tool\n'
+              'forwards the host port to a device port.');
     argParser.addOption('route',
         help: 'Which route to load when running the app.');
     usesTargetOption();
@@ -36,6 +42,7 @@ abstract class RunCommandBase extends FlutterCommand {
   }
 
   bool get traceStartup => argResults['trace-startup'];
+  bool get ipv6 => argResults['ipv6'];
   String get route => argResults['route'];
 
   void usesPortOptions() {
@@ -304,6 +311,7 @@ class RunCommand extends RunCommandBase {
         packagesFilePath: argResults['packages'],
         projectAssets: argResults['project-assets'],
         stayResident: stayResident,
+        ipv6: ipv6,
       );
     } else {
       runner = new ColdRunner(
@@ -314,6 +322,7 @@ class RunCommand extends RunCommandBase {
         applicationBinary: argResults['use-application-binary'],
         previewDart2: argResults['preview-dart-2'],
         stayResident: stayResident,
+        ipv6: ipv6,
       );
     }
 

packages/flutter_tools/lib/src/device.dart

@@ -227,6 +227,7 @@ abstract class Device {
     bool prebuiltApplication: false,
     bool applicationNeedsRebuild: false,
     bool usesTerminalUi: true,
+    bool ipv6: false,
   });
 
   /// Does this device implement support for hot reloading / restarting?

packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart

@@ -68,6 +68,7 @@ class FuchsiaDevice extends Device {
     bool previewDart2: false,
     bool applicationNeedsRebuild: false,
     bool usesTerminalUi: false,
+    bool ipv6: false,
   }) => new Future<Null>.error('unimplemented');
 
   @override

packages/flutter_tools/lib/src/ios/devices.dart

@@ -163,6 +163,7 @@ class IOSDevice extends Device {
     bool previewDart2: false,
     bool applicationNeedsRebuild: false,
     bool usesTerminalUi: true,
+    bool ipv6: false,
   }) async {
     if (!prebuiltApplication) {
       // TODO(chinmaygarde): Use mainPath, route.
@@ -255,7 +256,11 @@ class IOSDevice extends Device {
       // TODO(danrubel): The Android device class does something similar to this code below.
       // The various Device subclasses should be refactored and common code moved into the superclass.
       final ProtocolDiscovery observatoryDiscovery = new ProtocolDiscovery.observatory(
-        getLogReader(app: app), portForwarder: portForwarder, hostPort: debuggingOptions.observatoryPort);
+        getLogReader(app: app),
+        portForwarder: portForwarder,
+        hostPort: debuggingOptions.observatoryPort,
+        ipv6: ipv6,
+      );
 
       final Future<Uri> forwardObservatoryUri = observatoryDiscovery.uri;
 

packages/flutter_tools/lib/src/ios/simulators.dart

@@ -312,6 +312,7 @@ class IOSSimulator extends Device {
     bool prebuiltApplication: false,
     bool applicationNeedsRebuild: false,
     bool usesTerminalUi: true,
+    bool ipv6: false,
   }) async {
     if (!prebuiltApplication) {
       printTrace('Building ${app.name} for $id.');
@@ -352,7 +353,8 @@ class IOSSimulator extends Device {
 
     ProtocolDiscovery observatoryDiscovery;
     if (debuggingOptions.debuggingEnabled)
-      observatoryDiscovery = new ProtocolDiscovery.observatory(getLogReader(app: app));
+      observatoryDiscovery = new ProtocolDiscovery.observatory(
+          getLogReader(app: app), ipv6: ipv6);
 
     // Launch the updated application in the simulator.
     try {

packages/flutter_tools/lib/src/protocol_discovery.dart

@@ -5,6 +5,7 @@
 import 'dart:async';
 
 import 'base/common.dart';
+import 'base/io.dart';
 import 'base/port_scanner.dart';
 import 'device.dart';
 import 'globals.dart';
@@ -18,6 +19,7 @@ class ProtocolDiscovery {
     this.portForwarder,
     this.hostPort,
     this.defaultHostPort,
+    this.ipv6,
   }) : assert(logReader != null),
        assert(portForwarder == null || defaultHostPort != null),
        _prefix = '$serviceName listening on ' {
@@ -28,6 +30,7 @@ class ProtocolDiscovery {
     DeviceLogReader logReader, {
     DevicePortForwarder portForwarder,
     int hostPort,
+    bool ipv6: false,
   }) {
     const String kObservatoryService = 'Observatory';
     return new ProtocolDiscovery._(
@@ -35,6 +38,7 @@ class ProtocolDiscovery {
       portForwarder: portForwarder,
       hostPort: hostPort,
       defaultHostPort: kDefaultObservatoryPort,
+      ipv6: ipv6,
     );
   }
 
@@ -43,6 +47,7 @@ class ProtocolDiscovery {
   final DevicePortForwarder portForwarder;
   final int hostPort;
   final int defaultHostPort;
+  final bool ipv6;
 
   final String _prefix;
   final Completer<Uri> _completer = new Completer<Uri>();
@@ -90,6 +95,11 @@ class ProtocolDiscovery {
       hostUri = deviceUri.replace(port: hostPort);
     }
 
+    assert(new InternetAddress(hostUri.host).isLoopback);
+    if (ipv6) {
+      hostUri = hostUri.replace(host: InternetAddress.LOOPBACK_IP_V6.host);
+    }
+
     return hostUri;
   }
 }

packages/flutter_tools/lib/src/resident_runner.dart

@@ -273,6 +273,7 @@ class FlutterDevice {
       prebuiltApplication: prebuiltMode,
       applicationNeedsRebuild: shouldBuild || hasDirtyDependencies,
       usesTerminalUi: hotRunner.usesTerminalUI,
+      ipv6: hotRunner.ipv6,
     );
 
     final LaunchResult result = await futureResult;
@@ -316,9 +317,9 @@ class FlutterDevice {
       return 1;
     }
 
-    Map<String, dynamic> platformArgs;
+    final Map<String, dynamic> platformArgs = <String, dynamic>{};
     if (coldRunner.traceStartup != null)
-      platformArgs = <String, dynamic>{ 'trace-startup': coldRunner.traceStartup };
+      platformArgs['trace-startup'] = coldRunner.traceStartup;
 
     startEchoingDeviceLog();
 
@@ -332,6 +333,7 @@ class FlutterDevice {
       prebuiltApplication: prebuiltMode,
       applicationNeedsRebuild: shouldBuild || hasDirtyDependencies,
       usesTerminalUi: coldRunner.usesTerminalUI,
+      ipv6: coldRunner.ipv6,
     );
 
     if (!result.started) {
@@ -394,6 +396,7 @@ abstract class ResidentRunner {
     String packagesFilePath,
     String projectAssets,
     this.stayResident,
+    this.ipv6,
   }) {
     _mainPath = findMainDartFile(target);
     _projectRootPath = projectRootPath ?? fs.currentDirectory.path;
@@ -410,6 +413,7 @@ abstract class ResidentRunner {
   final DebuggingOptions debuggingOptions;
   final bool usesTerminalUI;
   final bool stayResident;
+  final bool ipv6;
   final Completer<int> _finished = new Completer<int>();
   bool _stopped = false;
   String _packagesFilePath;

packages/flutter_tools/lib/src/run_cold.dart

@@ -22,11 +22,13 @@ class ColdRunner extends ResidentRunner {
     this.applicationBinary,
     this.previewDart2 : false,
     bool stayResident: true,
+    bool ipv6: false,
   }) : super(devices,
              target: target,
              debuggingOptions: debuggingOptions,
              usesTerminalUI: usesTerminalUI,
-             stayResident: stayResident);
+             stayResident: stayResident,
+             ipv6: ipv6);
 
   final bool traceStartup;
   final String applicationBinary;

packages/flutter_tools/lib/src/run_hot.dart

@@ -45,6 +45,7 @@ class HotRunner extends ResidentRunner {
     String packagesFilePath,
     String projectAssets,
     bool stayResident: true,
+    bool ipv6: false,
   }) : super(devices,
              target: target,
              debuggingOptions: debuggingOptions,
@@ -52,7 +53,8 @@ class HotRunner extends ResidentRunner {
              projectRootPath: projectRootPath,
              packagesFilePath: packagesFilePath,
              projectAssets: projectAssets,
-             stayResident: stayResident);
+             stayResident: stayResident,
+             ipv6: ipv6);
 
   final String applicationBinary;
   final bool hostIsIde;

packages/flutter_tools/test/protocol_discovery_test.dart

@@ -104,47 +104,68 @@ void main() {
       testUsingContext('discovers uri if log line contains non-localhost', () async {
         initialize();
         final Future<Uri> uriFuture = discoverer.uri;
-        logReader.addLine('I/flutter : Observatory listening on http://somehost:54804/PTwjm8Ii8qg=/');
+        logReader.addLine('I/flutter : Observatory listening on http://127.0.0.1:54804/PTwjm8Ii8qg=/');
         final Uri uri = await uriFuture;
         expect(uri.port, 54804);
-        expect('$uri', 'http://somehost:54804/PTwjm8Ii8qg=/');
+        expect('$uri', 'http://127.0.0.1:54804/PTwjm8Ii8qg=/');
       });
     });
 
-    testUsingContext('port forwarding - default port', () async {
-      final MockDeviceLogReader logReader = new MockDeviceLogReader();
-      final ProtocolDiscovery discoverer = new ProtocolDiscovery.observatory(
-          logReader,
-          portForwarder: new MockPortForwarder(99),
-          hostPort: 54777);
-
-      // Get next port future.
-      final Future<Uri> nextUri = discoverer.uri;
-      logReader.addLine('I/flutter : Observatory listening on http://somehost:54804/PTwjm8Ii8qg=/');
-      final Uri uri = await nextUri;
-      expect(uri.port, 54777);
-      expect('$uri', 'http://somehost:54777/PTwjm8Ii8qg=/');
-
-      discoverer.cancel();
-      logReader.dispose();
-    });
+    group('port forwarding', () {
+      testUsingContext('default port', () async {
+        final MockDeviceLogReader logReader = new MockDeviceLogReader();
+        final ProtocolDiscovery discoverer = new ProtocolDiscovery.observatory(
+            logReader,
+            portForwarder: new MockPortForwarder(99),
+            hostPort: 54777);
+
+        // Get next port future.
+        final Future<Uri> nextUri = discoverer.uri;
+        logReader.addLine('I/flutter : Observatory listening on http://127.0.0.1:54804/PTwjm8Ii8qg=/');
+        final Uri uri = await nextUri;
+        expect(uri.port, 54777);
+        expect('$uri', 'http://127.0.0.1:54777/PTwjm8Ii8qg=/');
+
+        discoverer.cancel();
+        logReader.dispose();
+      });
+
+      testUsingContext('specified port', () async {
+        final MockDeviceLogReader logReader = new MockDeviceLogReader();
+        final ProtocolDiscovery discoverer = new ProtocolDiscovery.observatory(
+            logReader,
+            portForwarder: new MockPortForwarder(99),
+            hostPort: 1243);
+
+        // Get next port future.
+        final Future<Uri> nextUri = discoverer.uri;
+        logReader.addLine('I/flutter : Observatory listening on http://127.0.0.1:54804/PTwjm8Ii8qg=/');
+        final Uri uri = await nextUri;
+        expect(uri.port, 1243);
+        expect('$uri', 'http://127.0.0.1:1243/PTwjm8Ii8qg=/');
+
+        discoverer.cancel();
+        logReader.dispose();
+      });
+
+      testUsingContext('ipv6', () async {
+        final MockDeviceLogReader logReader = new MockDeviceLogReader();
+        final ProtocolDiscovery discoverer = new ProtocolDiscovery.observatory(
+            logReader,
+            portForwarder: new MockPortForwarder(99),
+            hostPort: 54777,
+            ipv6: true);
 
-    testUsingContext('port forwarding - specified port', () async {
-      final MockDeviceLogReader logReader = new MockDeviceLogReader();
-      final ProtocolDiscovery discoverer = new ProtocolDiscovery.observatory(
-          logReader,
-          portForwarder: new MockPortForwarder(99),
-          hostPort: 1243);
-
-      // Get next port future.
-      final Future<Uri> nextUri = discoverer.uri;
-      logReader.addLine('I/flutter : Observatory listening on http://somehost:54804/PTwjm8Ii8qg=/');
-      final Uri uri = await nextUri;
-      expect(uri.port, 1243);
-      expect('$uri', 'http://somehost:1243/PTwjm8Ii8qg=/');
-
-      discoverer.cancel();
-      logReader.dispose();
+        // Get next port future.
+        final Future<Uri> nextUri = discoverer.uri;
+        logReader.addLine('I/flutter : Observatory listening on http://127.0.0.1:54804/PTwjm8Ii8qg=/');
+        final Uri uri = await nextUri;
+        expect(uri.port, 54777);
+        expect('$uri', 'http://[::1]:54777/PTwjm8Ii8qg=/');
+
+        discoverer.cancel();
+        logReader.dispose();
+      });
     });
   });
 }